Firefox 40, due out in a couple of weeks, will be better adapted to Windows 10 than the current Firefox 39 release. Either way, it's a great idea to make a backup of your bookmarks and save them on external media or in the cloud. I suggest creating files in two different formats by using both the "backup" function and the "export" function. These articles have the steps: * [[Restore bookmarks from backup or move them to another computer]] * [[Export Firefox bookmarks to an HTML file to back up or transfer bookmarks]] More generally, you could back up your entire Firefox settings folder (profile folder). This article has some suggestions on that: [[Back up and restore information in Firefox profiles]].